In this paper, the authors have simulated pressure wave propagation in a closed system, considering the virtual mass force on the interphase border, the viscous shear force, the slippage velocity, and the narrow drag conditions. Based on the gas-liquid momentum conservation and mass conservation principles, the two-fluid model is established. To solve the model, considering the small disturbance principle and ignoring the second-order items, the basic equations are converted into vector form, and the final equation of velocity is obtained. The model is solved by the software program. The results show that with increase in porosity and decrease in the system pressure, temperature, and density of the liquid phase, the pressure wave propagation velocity decreases. With decrease in the low-frequency angular frequency, the slip velocity, and other factors that can slow down the gas-liquid exchange rate, the pressure wave velocity also decreases. With increase in the incompressibility of the gas-drilling fluid system and decrease in the interphase exchange time, the pressure wave propagation velocity increases. When the pressure wave frequency is low, the wave velocity is restricted mainly by the mechanical characteristics of the phase and the mechanism of thermodynamic balance.

在本文中，作者模拟了封闭系统中压力波的传播，考虑了相间边界上的虚拟质量力、粘性剪切力、滑移速度和窄阻力条件。基于气液动量守恒和质量守恒原理，建立了二流体模型。为求解模型，考虑小扰动原理，忽略二阶项，将基本方程转化为向量形式，得到最终的速度方程。该模型由软件程序求解。结果表明，随着孔隙率的增加和系统压力、温度和液相密度的降低，压力波传播速度减小。随着低频角频率的降低，滑移速度，等因素会减慢气液交换速度，压力波速也随之降低。随着气体钻井液体系不可压缩性的增加和相间交换时间的减少，压力波传播速度增加。当压力波频率较低时，波速主要受相的力学特性和热力平衡机制的限制。